Pacific Gas and Electric Co., accused by state regulators of destroying a potentially significant surveillance video taken in a gas-system control center the night of the San Bruno pipeline explosion, now says the recording never existed.

The California Public Utilities Commission recently charged the company with nearly 100 record-keeping and safety violations related to the Sept. 9, 2010, explosion and fire that killed eight people and destroyed 38 homes. Some of them concern a video recording that investigators believe could have shed new light on how PG&E's control center in Brentwood dealt with the crisis in the minutes before and after the blast happened.

For more than five months, PG&E said the video had been inadvertently recorded over. Then, in March, the company told state investigators that the recording system hadn't been configured properly the night of the explosion and that no video had been made.

An investigator for the utilities commission, which had demanded that PG&E turn over any video taken that night, said the company either was wrong when it gave its initial story, is wrong now, or both.

It's unclear what a video might have shown of what was happening in Brentwood as gas-system managers struggled first to understand why pressure on a Milpitas-to-San Francisco gas transmission line spiked uncontrollably, then plunged when the line ruptured in San Bruno.

PG&E confusion

Federal and state investigators' interviews of control-room personnel revealed that employees didn't know what had happened for more than half an hour after the explosion. The confusion contributed to a delay of 90 minutes in shutting off gas that was fueling the fire destroying a San Bruno neighborhood, investigators concluded.

"PG&E lacked detailed and comprehensive procedures for responding to a large-scale emergency such as a transmission line break," the National Transportation Safety Board concluded last year, "including a defined command structure that clearly assigns a single point of leadership and allocates specific duties to supervisory (control room) staff and other involved employees."

State and federal government probes of the San Bruno disaster are complete, but the state utilities commission opened a separate investigation into PG&E's gas-system records, which the blast investigations revealed to be in disarray.

Investigators with the commission's safety arm learned last year that there was a video camera in the Brentwood control center, aimed at a circle of desks where system controllers sat. It was not equipped with audio.

Changing story

PG&E initially said the video had been automatically recorded over sometime within about two months of the explosion, when the device's memory became full.

However, after the commission accused the company in January of failing to follow a state order to preserve evidence from the explosion - a charge that could result in significant fines - PG&E disavowed that story.

It said in March that the erasure explanation had been based on company officials' "mistaken belief" that a digital video recorder in the control center had been operating properly.

PG&E now says the contractor hired to replace the control room recorder in June 2010, Acme Security Systems of San Leandro, failed to program the motion-activated camera to the recorder, although it did properly link five other feeds from security cameras outside the center.

"Thus no video was overwritten," the company said in a statement to The Chronicle as well as in a written response to a utilities commission data request.

Margaret Felts, an independent expert working for the commission's safety arm, expressed skepticism about PG&E's new account in a filing to the five-member panel detailing alleged record-keeping violations.

She noted that "PG&E did not even check" the recorder to see whether it had been working before telling regulators that the video had been recorded over. That shows PG&E failed to try to carry out the commission's long-standing order to seek out and preserve all evidence related to the disaster, Felts said.

"Further investigation into the matter of the missing video records is recommended," Felts added.

'Serious situation'

Richard Kuprewicz, a pipeline safety consultant who has studied control room management, said the missing video is not a trivial matter.

"This is a very serious situation," said Kuprewicz, who has consulted for the consumer advocacy group The Utility Reform Network. "If you have a videotape and you have a major tragedy, and somebody didn't review that tape within a couple hours? This just raises all kinds of credibility questions."

Such video systems are not common, said Shamin Sharoki, head of a Texas firm, Consipio, that consults with the gas and oil industry on control room monitoring practices.

"A video is nice to have," Sharoki said. "If they had the data, they were obligated to keep it."

Charles Alday, a 45-year veteran of the pipeline industry whose company, Pipeline Performance Group, advises government and industry on control room management, said the controversy surrounding PG&E's video surveillance system raises larger questions.

"If you are going to do something related to a control room, you have to have a program and a procedure for training and documentation," Alday said. "The company had a catastrophic accident, and as a result, all of their procedures were called into question."

The video controversy and other PG&E problems that have been exposed following the blast, Alday said, show "some of the practices were not as good as they should be."

Phone records

PG&E is also under investigation by the state utilities commission for allegedly failing to produce recordings of 50 phone calls made from a control room in its San Francisco headquarters on the night of the disaster.

Within a month of the explosion, PG&E said it had turned over complete and unedited recordings of about 500 calls to and from the control room, but the commission's investigation revealed apparent gaps in the computerized audio files.

In January, Felts identified 50 calls for which PG&E had not turned over recordings.

The company has insisted it provided all the control room calls for the explosion investigation. Any missing calls came from elsewhere in company headquarters and had to do with subjects irrelevant to the blast, such as energy trading and marketing, PG&E says.

Felts said in her regulatory filing, however, that the company had failed to explain why such calls were made after business hours.